The Turborepo + Bun + Biome stack behind a 40-package monorepo

Forty packages, one maintainer, and no ESLint config anywhere in the repo. That is not a boast - it is the direct result of a decision made early: every tool in the toolchain has to earn its place by governing all forty packages from one config file, not forty. The repo is flare-engine , a modular 2D engine for React Native + Web (animation, gamification, interactive UI, with games as showcases - not a game engine, not a Unity or Godot competitor). The stack behind it is Turborepo Bun Biome , and this post is the actual setup: the real turbo.json , the real biome.json , the real CI guardrail, straight from the repo (trimmed only where a config is long, and I say so where I trim), not a starter template's idealized version. Four binaries, four root configs - turbo.json , biome.json , tsconfig.base.json , and the Changesets config - each governing all forty packages at once (Bun's own "config" is just the workspaces array in the root package.json ). Plus a CI step that fails the build the moment a package imports something it shouldn't. That is the whole story, and I want to show you the files, not describe them. Four binaries, not twelve config files The thesis is narrow: a solo maintainer can keep forty packages honest only if there is exactly one config of each kind, and every package extends it rather than declaring its own variant. Twelve packages each with a slightly different ESLint config is not a monorepo, it is twelve monorepos wearing a workspace file as a costume. Here is the root package.json that runs all of it - Bun workspaces (not pnpm; that distinction matters and I will say it again below), the script table every package leans on, and the pinned package manager: // C:\_PROG\flare-engine-workspace\flare-engine\package.json { "name" : "flare-engine" , "version" : "0.0.0" , "private" : true , "workspaces" : [ "packages/*" , "benchmarks" , "apps/*" ], "scripts" : { "build" : "turbo build" , "test" : "turbo test" , "lint" : "turbo lint" , "typecheck" : "t